nvme-rdma: Add IB event handling support

index 4d84a73..dc5af97 100644
@@ -45,6 +45,7 @@
 struct nvme_rdma_device {
 	struct ib_device	*dev;
 	struct ib_pd		*pd;
+	struct ib_event_handler	event_handler;
 	struct kref		ref;
 	struct list_head	entry;
 };

@@ -329,6 +330,7 @@ static void nvme_rdma_free_dev(struct kref *ref)
 	list_del(&ndev->entry);
 	mutex_unlock(&device_list_mutex);
 
+	ib_unregister_event_handler(&ndev->event_handler);
 	ib_dealloc_pd(ndev->pd);
 	kfree(ndev);
 }

@@ -343,6 +345,36 @@ static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
 	return kref_get_unless_zero(&dev->ref);
 }
 
+static void nvme_rdma_ib_event_handler(struct ib_event_handler *handler,
+				       struct ib_event *event)
+{
+	struct nvme_rdma_ctrl *ctrl;
+	int i;
+
+	pr_debug("async event %s (%d) on device %s port %d\n",
+		 ib_event_msg(event->event), event->event,
+		 event->device->name, event->element.port_num);
+
+	switch(event->event) {
+	case IB_EVENT_DEVICE_FATAL:
+		mutex_lock(&nvme_rdma_ctrl_mutex);
+		list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list) {
+			if (ctrl->device->dev != event->device)
+				continue;
+
+			for (i = 0; i < ctrl->ctrl.queue_count; i++)
+				clear_bit(NVME_RDMA_Q_LIVE,
+					  &ctrl->queues[i].flags);
+			nvme_delete_ctrl(&ctrl->ctrl);
+		}
+		mutex_unlock(&nvme_rdma_ctrl_mutex);
+		break;
+	default:
+		pr_debug("Unsupported event (%d)\n", event->event);
+		break;
+	}
+}
+
 static struct nvme_rdma_device *
 nvme_rdma_find_get_device(struct rdma_cm_id *cm_id)
 {

@@ -374,6 +406,10 @@ static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
 		goto out_free_pd;
 	}
 
+	INIT_IB_EVENT_HANDLER(&ndev->event_handler, ndev->dev,
+	                      nvme_rdma_ib_event_handler);
+	ib_register_event_handler(&ndev->event_handler);
+
 	list_add(&ndev->entry, &device_list);
 out_unlock:
 	mutex_unlock(&device_list_mutex);